Ive read a few things suggesting that it would be a good idea to run a hardened intermediate shaft with a HV oil pump. Is this true? And if so can I just get a new one and simply install it? I have a new bushing for the intermediate shaft already installed. Or will that have to be replaced...?
Do I need a hardened intermediate shaft for a HV oil pump?
- Thread starter DartVadar
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It's not a suggestion. It is a requirement.
Guess this was a good question to ask...lol
Well glad I figured it out while I still have the engine on the stand. I can see how it could tear up the gears. So can I just put the new intermediate shaft in or does the bushing need to be changed?
So I take it it's just a standard part I could order from summit, Any particular one that's better?
omahamoparguy
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...yes...you need hardened. also remember that some of the new bushing might need to be "reamed" to size. usually if the old bushing is good, I would reuse it if it is in good shape. Don't know where you would find the reamer for the bushing. Anyone know...? In any case, check the fitment of the shaft to the bushing real good...
TrailBeast
AKA Mopars4us on Youtube
That was the post about the reamer.
May need it, may not and you won't know until you fit it.
It is not about tearing up the gears...it is about the hex end of the shaft rounding out under the load of the HV pump....the harden shaft hex end will not round out....
there is a billet intermediate shaft available on ebay............and can not find them for sale tonight....LOL
guy sells blueprinted melling oil pumps and billet shafts...the shafts are only 39 bucks....over in Bakersfield ca.
Well hopefully I don't need to ream it. I primed the engine today because I just wanted to make sure everything was getting oil before I drop it in this weekend (planning on priming it again before I start it too). The primer was made from an old intermediate shaft with a rod welded to it. It fit into the bushing really nice, I measure it with a caliper and it's the same size as my old intermediate shaft that I now am definitely not using!
If the old one fits wouldn't that technically mean that the new intermediate shaft should as well? If I have to ream it I will, but what's the best way to do that? Take out the bushing to not get crap everywhere?
What would be a good intermediate shaft to get, is there a common one that's decently priced but still good?
If the old one fits wouldn't that technically mean that the new intermediate shaft should as well? If I have to ream it I will, but what's the best way to do that? Take out the bushing to not get crap everywhere?
What would be a good intermediate shaft to get, is there a common one that's decently priced but still good?
Ahh I see, I was looking at my old one and the hex end has some noticable wear on it, would probably have been a good idea to replace it anyways.
Now what about the gears? Does that really matter? It's a new comp cam, and I guess now I'll have a new hardened intermediate shaft.
As long as it is an aftermarket (not Chrysler) bushing, it will not need reaming with the special tool. The aftermarket bushings are sized so that when they are installed they are the correct inside diameter.
At least I think it was replaced it looks to be made of brass, would that be something that a machine shop would do when they bore/prep a block? If not then I guess it's the original one...if so that means it will have to be reamed? Can this be done without taking the motor apart? Or is that inevitable if the shaft doesn't fit?
daliant
Befuddled
All depends on how "tight" the engine is, those high volume oil pumps were meant for those quicky backyard re-ring jobs on the cheep where the bearing and lifter bore tolerances where at the high ends of their limits and the extra volume kept the oil pressure up while hot at idle or race engines with intentionally loose tolerances and big oil pans. If this is a proper rebuild where bearing clearances are within spec and everything is good and tight and you don't plan on spinning the thing up past 5500 rpm then a hv oil pump isn't the hot ticket. The hv oil pump puts more stress on the intermediate shaft especially on a tight engine running thick oil so like others have posted if you'r going to run the hv pump use the hardened shaft.
That makes sense, and I know I don't need a HV pump at all, I just already had one so I thought I'd use it, the engine is brand new as well. Well next time I think I'll just use a regular pump.
Never would have guessed a little intermediate should would be cause for concern. Well I'll order a hardened one and hope it fits the bushing, if not, well then I'll have to ream it or something.
I've run the harder shaft with the new bushing and it was fine.
When installing the intermediate shaft bushing per factory spec, you do not "ream" the bushing at all, best descriptor I can think of is a combination of rolling and burnishing. The rolling action locks the bushing in place by expanding it and the burnishing action smooths the interior and size's it. If you're reaming and cutting metal; you're doing something wrong.
Running a hardened intermediate shaft is never a bad idea.
Don't have the tool? Get friendly with the service manager at your local Chyrslier dealer and borrow theirs.
Running a hardened intermediate shaft is never a bad idea.
Don't have the tool? Get friendly with the service manager at your local Chyrslier dealer and borrow theirs.
BigBlockMopar
BigBlockMember
On a new, tight engine and a HV oilpump you might end up with too much oilpressure, depending on the oilweight you use because the oilpump can't 'get rid of the oil' fast enough so pressure could rise.
Be prepared to switch to a thinner oil or weaker pressure-spring in the pump after the break-in if needed.
Be prepared to switch to a thinner oil or weaker pressure-spring in the pump after the break-in if needed.
sst3193
Well-Known Member
Don't forget the high quality oil filter. Big volume oil pumps can destroy a cheap filter, I found out.
I bought a blue printed HV pump years ago. It get pressure very quickly when starting. One of the best investments that I've made.
Couple things here, there is a difference in an HV and HP pump. "Most" high volume pumps do NOT come with the high pressure spring installed, so out of the box, a melling ***-HV is high volume, standard pressure. Sure they make more pressure than a $15 napa OEM replacement, but thats not their intention unless you swap the springs.
next, the hardened shaft is a requirement with an HV pump as pointed out above..but i have never had to ream a shaft bushing. you should have enough clearence.
lastly, as daliant pointed out above, the HV pump is really for performance engines. If you put this in an engine with a STOCK 5qt capacity pan, you're going to suck the pan dry at high RPM. you'll need an aftermarket pan with 6-8 quarts to be safe. unless you never go above 4500RPM. you might want to invest in a $40 OEM style pump, before you spend 2-300 on a oil pan.
next, the hardened shaft is a requirement with an HV pump as pointed out above..but i have never had to ream a shaft bushing. you should have enough clearence.
lastly, as daliant pointed out above, the HV pump is really for performance engines. If you put this in an engine with a STOCK 5qt capacity pan, you're going to suck the pan dry at high RPM. you'll need an aftermarket pan with 6-8 quarts to be safe. unless you never go above 4500RPM. you might want to invest in a $40 OEM style pump, before you spend 2-300 on a oil pan.
First off lets think about this logically. High Volume dose not mean high pressure. If the engine dose not need the volume the relief valve dumps the excess right back in the pan. If the bearing clearances are big where dose the extra oil go.. right back in the pan. The only time you would suck the pan dry is if you were restricting the drain back from the heads.... Next again a high volume pump dose not put any more strain on the pump drive than a standard pump so it will not break a drive any faster than a standard pump. If you install a high pressure spring or in some way stop the relief vavle from doing its job then you are putting more strain on the pump drive.
So you figure it out for your situation. Me I use HV pumps on all my rebuilds just because I will know I'm getting plenty of oil to all areas and I don't go out of my way to put the hardend drive in unless I have it handy.
PS I have never had a drive fail in 35 years of oval track racing..my engines see 7k every lap.
So you figure it out for your situation. Me I use HV pumps on all my rebuilds just because I will know I'm getting plenty of oil to all areas and I don't go out of my way to put the hardend drive in unless I have it handy.
PS I have never had a drive fail in 35 years of oval track racing..my engines see 7k every lap.
nm9stheham
Well-Known Member
Interesting above. Thinking logically, moving more volume at the same pressure requires more work and so more load will need to be on the pump's drive shaft, regardless of where that extra oil goes.
Just a thought: Perhaps your success with non-hardended shafts is because you rebuild and change things out pretty often.
Your excellent racing experience is great to hear. But oil starvation also depends on the duration of the high perssure/high flow situation. You could be approaching oil starvation 2x per lap, but never reach it due to letting off after a short time each time you rev it. I built an engine once with a high volume pump and a high pressure spring when I was younger, on an engine that had never had oil problems. I revved it I bet a thousand times for short durations to 6k-8k but then on the first very long duration high RPM situation, the oil overpumped to the heads and the engine starved from oil. So, short duration revs is not proof that oil starvation is not a possible problem on a given engine.
Just a thought: Perhaps your success with non-hardended shafts is because you rebuild and change things out pretty often.
Your excellent racing experience is great to hear. But oil starvation also depends on the duration of the high perssure/high flow situation. You could be approaching oil starvation 2x per lap, but never reach it due to letting off after a short time each time you rev it. I built an engine once with a high volume pump and a high pressure spring when I was younger, on an engine that had never had oil problems. I revved it I bet a thousand times for short durations to 6k-8k but then on the first very long duration high RPM situation, the oil overpumped to the heads and the engine starved from oil. So, short duration revs is not proof that oil starvation is not a possible problem on a given engine.
I have a melling high volume pump on it right now, and I assume it doesn't have the high pressure spring that was mentioned. Good to hear that I shouldn't have any issue with the bushing, seems like once I get the new hardened intermediate shaft I I'll just drop it in and go.
Besides my old intermediate shaft is showing some wear, best to change it anyways.
And about the oil starvation, it does seem like that could be a problem. But fortunately for me I have an 8 quart moroso pan on there, should have plenty oil to not suck it dry.
Besides my old intermediate shaft is showing some wear, best to change it anyways.
And about the oil starvation, it does seem like that could be a problem. But fortunately for me I have an 8 quart moroso pan on there, should have plenty oil to not suck it dry.
Reamed, rolled, burnished. What's the difference as long as he uses the right tool? Like I told him, if he uses the aftermarket bushing, they require nothing but installation and they are ready to GO.
This is simply not true. The more volume of oil you move, the more resistance you have. Very simple to test with a drill and a priming tool. The HV pump will have MUCH more resistance than a stock volume. If what you said above is true, there would be no need for companies to make hardened oil pump shafts and no need to buy them. You are mistaken. Please don't give people wrong information. They might use it and destroy something. Just because you've done something for 35 years at 7K RPM doesn't make it right. You might try cracking a book now and then.
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